密度泛函理论研究KB_n(n=1-9)团簇的结构和性质  

Density functional theory study on the structures and properties of KB_n( n = 1-9) clusters

作　　者：孙凌涛[1] 郭朝中[1] 石东平[1] 

机构地区：[1]重庆文理学院新材料技术研究院,重庆402160

出　　处：《原子与分子物理学报》2015年第6期977-982,共6页Journal of Atomic and Molecular Physics

基　　金：重庆文理学院校级科研项目(Y2013CJ26;R2014CJ02;Y2014CJ24);重庆市基础与前沿研究计划项目(cstc2014jcyj A50038);重庆市高校微纳米材料工程与技术重点实验室度开放课题(KFJJ1404)

摘　　要：在密度泛函理论的框架下,采用广义梯度近似(GGA)研究了KB_n(n=1-9)团簇的基态几何结构,系统计算了平均结合能Eb、二阶能量差分△2E、劈裂能D(n,n-1)、最高占据轨道(HOMO)与最低未占据轨道(LUMO)之间的能隙,研究表明:KB_n(n=1-9)团簇,随着团簇尺寸的变化,其稳定性逐渐增强,其中KB_3和KB_5为幻数团簇;KB_n(n=1-9)团簇的能隙随团簇总原子数的增加呈现振荡变化,态密度分析得到能隙振荡变化的原因是团簇带隙的差异.The ground state geometry structures of the KB_n（ n = 1- 9） clusters are studied by using the generalized gradient approximation（ GGA） based on the density functional theory framework. We have systematically calculated the binding energy per atom（ Eb）,the second- order difference of energy（ △2E）,splitting energy（ 9D（ n,n- 1））,and the gap between the highest occupy orbit（ HOMO） and the lowest unoccupy orbit（ LUMO）. The results indicate that with the change in size of KBn（ n = 1- 9） clusters,its stability will be gradually increased,where KB_3 and KB_5 are attributed to magic number clusters. The energy gap of KB_n（ n = 1- 9） clusters presents the change of oscillation with the increasing of the total number of atom. Besides,the analysis of density of states suggests that the change of oscillation is due to the gap difference of clusters.

关 键 词：团簇 稳定结构 密度泛函理论 态密度 

分 类 号：O561[理学—原子与分子物理]